The present invention relates to a liquid crystal display having a built-in photoelectric conversion device.
Liquid crystal displays have been broadly used due to the advantages of their energy saving construction and light-weight compact structure. Particularly, these displays are suitable for lap-top personal computors or wordprocessors. There are two types of liquid crystal display devices, i.e. the reflective type and the transmissive type. In the construction of the reflective type, light enters into the liquid crystal layer from the front surface of the display on which visual images are constructed. The incident light is reflected on the rear side of the liquid crystal layer and then emitted from the front surface after modulated through the liquid crystal layer. In the construction of the transmissive type, light enters from the rear surface of the liquid crystal layer and exits from the front surface thereof. Usually, a light source is provided in the rear side of the liquid crystal layer in order to supply light rays to the liquid crystal display in this case.
The transmissive type is advantageous as compared with the reflective type in that the light source employed in the transmissive type can make the images bright and clear and can make it possible to construct colour images which can not be realized in case of the reflective type because of lack of sufficient brightness. However, the provision of the light source makes the display expensive and heavy.